31 Days of Halloween - Day 6

Monster: Unnamed alien entity

Appearance: "Terror of the Sierra Madre"  The Adventures of Superman Annual #9. 1997.
Alcatena: Artist, Phil Felix: Letterer, Glenn Whitmore: Colorist, Digital Chameleon: Separators, Mike McAvennie: Associate Editor, Joey Cavalieri: Editor

The alien in this story is incredibly ancient. Imprisoned deep within the forming earth by its own race, it was finally able to emerge from beneath the Sierra Madres about a thousand years ago. There it terrorized all of Mexico, building back its strength by essentially devouring entire cultures, including the Olmec, Mogollon, and the Anasazi. The humans fought back, weakening it sufficiently that it had to take refuge in one of the humans who was then encased in an olla, or clay pot and buried deep within the earth, where it lay dormant until an archeological team discovers it.

This was during the time when Superman was divided into two beings: Superman Red, and Superman Blue, where his powers were different and Clark Kent needed to transform into Superman in order to use his new super senses. You can look it up. I don't remember all of the dynamics.

Anyway, the entity is freed and makes his way through the archeological team, jumping from one body to the next, using them as its tool until they are desiccated husks that he disposes of by jumping to the next victim. He also has the ability to levitate, control and transform others, including the local coyote population, and  alter his own appearance as seen here:

His goal was to take over Superman and give himself a supercharge by absorbing his energy. Little did the alien entity know that Superman's new powers worked in a very similar fashion, and the alien agreed to be exiled from earth forever rather than be fatally absorbed within Superman's body.

Yes, there's a bit of Chariots of the Gods here, with an X-Files-type explanation for the disappearance of entire cultures. This makes sense since I was also writing The X-Files comic book at this time. so research and mood from one spilled over into the other, which came about when Joey Cavalieri asked me to provide a Western themed Superman story. It's actually one of the few extraterrestrial related stories I've ever written.